Jupiter's Outer Moons Jupiter's Outer Moons Sinope Jupiter's eight outer moons fall into two groups: Leda, Himalia, Lysithea and Elara at about 11 million km from Jupiter and Ananke, Carme, Pasiphae and Sinope at about 23 million km. When the first version of The Nine Planets was written that was it. But in recent years several dozen tiny moons in various orbits farther out have been detected. Leda Leda ("LEE duh") is the ninth of Jupiter's known satellites and the smallest: orbit : 11,094,000 km from Jupiter diameter : 16 km mass : 5.68e15 kg Leda was queen of Sparta and the mother, by Zeus in the form of a swan, of Pollux and Helen of Troy. Discovered by Kowal in 1974. Leda, Ananke, and Sinope are among the smallest moons in the solar system.

Himalia Himalia ("hih MAL yuh") is the tenth of Jupiter's known satellites: orbit : 11,480,000 km from Jupiter diameter : 186 km mass : 9.56e18 kg Himalia was a nymph who bore three sons of Zeus (Jupiter). Discovered by Perrine in 1904. Unlike the inner satellites, the orbits of Leda, Himalia, Lysithea and Elara are significantly inclined to Jupiter's equator (about 28 degrees). Lysithea Lysithea ("ly SITH ee uh") is the eleventh of Jupiter's known satellites: orbit : 11,720,000 km from Jupiter diameter : 36 km mass : 7.77e16 kg Lysithea was a daughter of Oceanus and one of Zeus' lovers. Discovered by Nicholson in 1938.

Elara Elara ("EE lar uh") is the twelfth of Jupiter's known satellites: orbit : 11,737,000 km from Jupiter diameter : 76 km mass : 7.77e17 kg Elara was the mother by Zeus of the giant Tityus. Discovered by Perrine in 1905. Leda, Himalia, Lysithea and Elara may be remnants of a single asteroid that was captured by Jupiter and broken up. Ananke Ananke ("a NANG kee") is the thirteenth of Jupiter's known satellites: orbit : 21,200,000 km from Jupiter diameter : 30 km mass : 3.82e16 kg Ananke was the mother of Adrastea, by Jupiter. Discovered by Nicholson in 1951. Ananke, Carme, Pasiphae and Sinope have unusual but similar orbits.

Carme Carme ("KAR mee") is the fourteenth of Jupiter's known satellites: orbit : 22,600,000 km from Jupiter diameter : 40 km mass : 9.56e16 kg Carme was the mother, by Zeus of Britomartis, a Cretan goddess. Discovered by Nicholson in 1938. Ananke, Carme, Pasiphae and Sinope are especially unusual in that their orbits are retrograde . Pasiphae Pasiphae ("pah SIF ah ee") is the fifteenth of Jupiter's known satellites: orbit : 23,500,000 km from Jupiter diameter : 50 km mass : 1.91e17 kg Pasiphae was the wife of Minos and mother, by a white bull, of the Minotaur. Discovered by P. Melotte in 1908. Ananke, Carme, Pasiphae and Sinope have orbits highly inclined to Jupiter's equator (about 150 degrees).

Sinope Sinope ("sah NOH pee") is the outermost of Jupiter's known confirmed satellites: orbit : 23,700,000 km from Jupiter diameter : 36 km mass : 7.77e16 kg Sinope was a woman said to have been unsuccessfully (!) courted by Zeus. Discovered by Nicholson in 1914. Ananke, Carme, Pasiphae and Sinope may be remnants of a single asteroid that was captured by Jupiter and broken up. Open Issues Why do they fall into two distinct groups? Are they indeed captured asteroids? We know next to nothing about these moons. Even the basic mass and size data are not very accurate. Jupiter's Outer Moons Jupiter's Outer Moons Jupiter's eight outer moons fall into two groups: Leda, Himalia, Lysithea and Elara at about 11 million km from Jupiter and Ananke, Carme, Pasiphae and Sinope at about 23 million km.

Leda Leda ("LEE duh") is the ninth of Jupiter's known satellites and the smallest: orbit : 11,094,000 km from Jupiter diameter : 16 km mass : 5.68e15 kg Leda was queen of Sparta and the mother, by Zeus in the form of a swan, of Helen and Pollux. Discovered by Kowal in 1974. Leda, Ananke, and Sinope are among the smallest moons in the solar system. Himalia Himalia ("hih MAL yuh") is the tenth of Jupiter's known satellites: orbit : 11,480,000 km from Jupiter diameter : 186 km mass : 9.56e18 kg Himalia was a nymph who bore three sons of Zeus (Jupiter). Discovered by Perrine in 1904. Unlike the inner satellites, the orbits of Leda, Himalia, Lysithea and Elara are significantly inclined to Jupiter's equator (about 28 degrees).

Lysithea Lysithea ("ly SITH ee uh") is the eleventh of Jupiter's known satellites: orbit : 11,720,000 km from Jupiter diameter : 36 km mass : 7.77e16 kg Lysithea was a daughter of Oceanus and one of Zeus' lovers. Discovered by Nicholson in 1938. Elara Elara ("EE lar uh") is the twelfth of Jupiter's known satellites: orbit : 11,737,000 km from Jupiter diameter : 76 km mass : 7.77e17 kg Elara was the mother by Zeus of the giant Tityus. Discovered by Perrine in 1905. Leda, Himalia, Lysithea and Elara may be remnants of a single asteroid that was captured by Jupiter and broken up.

Ananke Ananke ("a NANG kee") is the thirteenth of Jupiter's known satellites: orbit : 21,200,000 km from Jupiter diameter : 30 km mass : 3.82e16 kg Ananke was the mother of Adrastea, by Jupiter. Discovered by Nicholson in 1951. Ananke, Carme, Pasiphae and Sinope have unusual but similar orbits. Carme Carme ("KAR mee") is the fourteenth of Jupiter's known satellites: orbit : 22,600,000 km from Jupiter diameter : 40 km mass : 9.56e16 kg Carme was the mother, by Zeus of Britomartis, a Cretan goddess. Discovered by Nicholson in 1938. Ananke, Carme, Pasiphae and Sinope are especially unusual in that their orbits are retrograde .

Pasiphae Pasiphae ("pah SIF ah ee") is the fifteenth of Jupiter's known satellites: orbit : 23,500,000 km from Jupiter diameter : 50 km mass : 1.91e17 kg Pasiphae was the wife of Minos and mother, by a white bull, of the Minotaur. Discovered by P. Melotte in 1908. Ananke, Carme, Pasiphae and Sinope have orbits highly inclined to Jupiter's equator (about 150 degrees). Sinope Sinope ("sah NOH pee") is the outermost of Jupiter's known satellites: orbit : 23,700,000 km from Jupiter diameter : 36 km mass : 7.77e16 kg Sinope was a woman said to have been unsuccessfully (!) courted by Zeus. Discovered by Nicholson in 1914. Ananke, Carme, Pasiphae and Sinope may be remnants of a single asteroid that was captured by Jupiter and broken up. Open Issues Why do they fall into two distinct groups? Are they indeed captured asteroids?

We know next to nothing about these moons. Even the basic mass and size data are not very accurate. Jupiter's Outer Moons Jupiter's Outer Moons Sinope Jupiter's eight outer moons fall into two groups: Leda, Himalia, Lysithea and Elara at about 11 million km from Jupiter and Ananke, Carme, Pasiphae and Sinope at about 23 million km. When the first version of The Nine Planets was written that was it. But in recent years several dozen tiny moons in various orbits farther out have been detected. Leda Leda ("LEE duh") is the ninth of Jupiter's known satellites and the smallest: orbit : 11,094,000 km from Jupiter diameter : 16 km mass : 5.68e15 kg Leda was queen of Sparta and the mother, by Zeus in the form of a swan, of Pollux and Helen of Troy. Discovered by Kowal in 1974. Leda, Ananke, and Sinope are among the smallest moons in the solar system.

Himalia Himalia ("hih MAL yuh") is the tenth of Jupiter's known satellites: orbit : 11,480,000 km from Jupiter diameter : 186 km mass : 9.56e18 kg Himalia was a nymph who bore three sons of Zeus (Jupiter). Discovered by Perrine in 1904. Unlike the inner satellites, the orbits of Leda, Himalia, Lysithea and Elara are significantly inclined to Jupiter's equator (about 28 degrees). Lysithea Lysithea ("ly SITH ee uh") is the eleventh of Jupiter's known satellites: orbit : 11,720,000 km from Jupiter diameter : 36 km mass : 7.77e16 kg Lysithea was a daughter of Oceanus and one of Zeus' lovers. Discovered by Nicholson in 1938.

Elara Elara ("EE lar uh") is the twelfth of Jupiter's known satellites: orbit : 11,737,000 km from Jupiter diameter : 76 km mass : 7.77e17 kg Elara was the mother by Zeus of the giant Tityus. Discovered by Perrine in 1905. Leda, Himalia, Lysithea and Elara may be remnants of a single asteroid that was captured by Jupiter and broken up. Ananke Ananke ("a NANG kee") is the thirteenth of Jupiter's known satellites: orbit : 21,200,000 km from Jupiter diameter : 30 km mass : 3.82e16 kg Ananke was the mother of Adrastea, by Jupiter. Discovered by Nicholson in 1951. Ananke, Carme, Pasiphae and Sinope have unusual but similar orbits.

Carme Carme ("KAR mee") is the fourteenth of Jupiter's known satellites: orbit : 22,600,000 km from Jupiter diameter : 40 km mass : 9.56e16 kg Carme was the mother, by Zeus of Britomartis, a Cretan goddess. Discovered by Nicholson in 1938. Ananke, Carme, Pasiphae and Sinope are especially unusual in that their orbits are retrograde . Pasiphae Pasiphae ("pah SIF ah ee") is the fifteenth of Jupiter's known satellites: orbit : 23,500,000 km from Jupiter diameter : 50 km mass : 1.91e17 kg Pasiphae was the wife of Minos and mother, by a white bull, of the Minotaur. Discovered by P. Melotte in 1908. Ananke, Carme, Pasiphae and Sinope have orbits highly inclined to Jupiter's equator (about 150 degrees).

Sinope Sinope ("sah NOH pee") is the outermost of Jupiter's known confirmed satellites: orbit : 23,700,000 km from Jupiter diameter : 36 km mass : 7.77e16 kg Sinope was a woman said to have been unsuccessfully (!) courted by Zeus. Discovered by Nicholson in 1914. Ananke, Carme, Pasiphae and Sinope may be remnants of a single asteroid that was captured by Jupiter and broken up. Open Issues Why do they fall into two distinct groups? Are they indeed captured asteroids? We know next to nothing about these moons. Even the basic mass and size data are not very accurate. Moons Moons: Moons are `fossils" into a planet's past.

The major, named moon systems are: Earth: Luna (The Moon) Mars: Deimos, Phobos Jupiter: Adrastea, Amalthea, Ananke, Callisto, Carme, Elara, Europa, Ganymede, Himalia, Io, Leda, Lysithea, Metis, Pasiphae, Sinope, Thebe Saturn: Atlas, Calypso, Dione, Enceladus, Epimetheus, Helene, Hyperion, Iapetus, Janus, Mimas, Pan, Pandora, Phoebe, Prometheus, Rhea, Telesto, Tethys, Titan Uranus: Ariel, Belinda, Bianca, Cordelia, Cressida, Desdemona, Juliet, Miranda, Oberon, Ophelia, Portia, Puck, Rosalind, Titania, Umbriel Neptune: Despina, Galatea, Larissa, Naiad, Nereid, Proteus, Thalassa, Triton Pluto: Charon (note: Pluto/Charon form a binary system, but Charon is the smaller so it is classed as the moon of Pluto) New, smaller moons are being discovered all the

 time with recent space missions.

The total count of moons (as of 12/18/2001) are: Mercury - 0 moons Mars - 2 moons Uranus - 20 moons Venus - 0 moons Jupiter - 28 moons Neptune - 8 moons Earth - 1 moon Saturn - 30 moons Pluto - 1 moon Moons range in shape from highly irregular to spheres. Their shape reflects their formation history, irregular objects are ill-formed moons (captured asteroids or comets) or pieces of a larger moon, spherical objects were once molten spheres, probably at the time of their formation. Moons of Mars: Deimos & Phobos We speculate, from their irregular appearances and low mean densities, that Deimos and Phobos, are captured asteroids. Both Deimos and Phobos are saturated with craters. Deimos has a smoother appearance caused by partial filling of some of its craters. Moons of Jupiter: Jupiter has 63 confirmed moons as of Jan 2009, i.e. moons with known orbits around Jupiter. Eight of these moons are regular, meaning they have prograde, nearly circular orbits.

They are composed of the four Galilean satellites, plus the inner or Amalthea group: Adrastea is a typical small moon Metis is the innermost known satellite of Jupiter Amalthea is one of Jupiter's smaller, irregular moons, an example of moon collecting dust from another moon (Io) The remaining 55 moons are irregular, they have a mixture of prograde and retrograde orbits with high inclinations and eccentricities. Jupiter's regular satellites are believed to have formed from a circumplanetary disk, a ring of accreting gas and solid debris analogous to a protoplanetary disk. The irregular satellites are substantially smaller objects with more distant and eccentric orbits. They form families with shared similarities in orbit (semi-major axis, inclination, eccentricity) and composition; it is believed that these are at least partially collisional families that were created when larger (but still small) parent bodies were shattered by impacts from asteroids captured by Jupiter's gravitational field. Moons of Saturn: The moons of Saturn are numerous and diverse, ranging from tiny moonlets less than 1 kilometer across to the enormous Titan, which is larger than the planet Mercury.

Saturn has sixty-two moons with confirmed orbits, fifty-three of which have names, and only thirteen of which have diameters larger than 50 kilometers. Saturn has seven moons that are large enough to become spherical. Twenty-four of Saturn's moons are regular satellites; they have prograde orbits not greatly inclined to the Saturn's equatorial plane. These include the seven major satellites, four small moons which exist in a Trojan orbit with larger moons, two mutually co-orbital moons and two moons which act as shepherds of Saturn's F Ring. Two other known regular satellites orbit within gaps in Saturn's rings. The relatively large Hyperion is locked in a resonance with Titan. The remaining regular moons orbit near the outer edge of the A Ring, within G Ring and between the major moons Mimas and Enceladus. The regular satellites are traditionally named after Titans and Titanesses or other figures associated with the mythological Saturn. The remaining thirty-eight, all small except one, are irregular satellites, whose orbits are much farther from Saturn, have high inclinations, and are mixed between prograde and retrograde. These moons are probably captured minor planets, or debris from the breakup of such bodies after they were captured, creating collisional families.

The irregular satellites have been classified by their orbital characteristics into the Inuit, Norse, and Gallic groups, and their names are chosen from the corresponding mythologies. The largest of the irregular moons is Phoebe, the ninth moon of Saturn, discovered at the end of the 19th century. The rings of Saturn are made up of objects ranging in size from microscopic to hundreds of meters, each of which is on its own orbit about the planet. Thus, a precise number of Saturnian moons cannot be given, as there is no objective boundary between the countless small anonymous objects that form Saturn's ring system and the larger objects that have been named as moons. At least 150 moonlets embedded in the rings have been detected by the disturbance they create in the surrounding ring material, though this is thought to be only a small sample of the total population of such objects. Daphnis drifts through the Keeler gap Atlas the second of Saturn's known satellites, orbits near the outer edge of the A-ring Enceladus is one of the innermost moons of Saturn.

Enceladus reflects almost 100 percent of the sunlight that strikes it and has evidence of internal heating and recent resurfacing effects Hyperion is one of the smaller moons of Saturn. It has a pock-marked body and is the largest irregularly shaped satellite ever observed.

Iapetus is one of the stranger moons of Saturn, its leading side is dark with a slight reddish color while its trailing side is bright Dione is the densest moon of Saturn other than Titan, and has several usual characteristics: 1) has a rocky core and ice crust, 2) is heavy cratering on trailing hemisphere, 3) has bright, wispy features Rhea is the largest airless satellite of Saturn that has different regions with different crater sizes indicating that parts of the moon have undergone resurfacing since formation Mimas is one of the innermost moons of Saturn with a very large impact crater that came close to fracturing the moon Tethys is an icy body similar in nature to Dione and Rhea Phoebe is the last of the known satellites of Saturn and orbits in a retrograde direction (opposite to the direction of the other satellites' orbits) in a plane much closer to the ecliptic than to Saturn's equatorial plane. Thus, Phoebe may be a captured asteroid with a composition unmodified since the time it was formed in the outer Solar System.

Moons of Uranus: Uranus, the seventh planet of the Solar System, has 27 known moons, all of which are named after characters from the works of William Shakespeare and Alexander Pope. William Herschel discovered the first two moons, Titania and Oberon, in 1787, and the other spherical moons were discovered in 1851 by William Lassell (Ariel and Umbriel) and in 1948 by Gerard Kuiper (Miranda). The remaining moons were discovered after 1985, either during the Voyager 2 flyby mission or with the aid of advanced Earth-based telescopes. A montage of Uranus' large moons and one smaller moon: from left to right Puck, Miranda, Ariel, Umbriel, Titania and Oberon. Uranian moons are divided into three groups: thirteen inner moons, five major moons, and nine irregular moons. The inner moons are small dark bodies that share common properties and origins with the planet's rings. The five major moons are massive enough to have achieved hydrostatic equilibrium (they were once molten spheres), and four of them show signs of internally driven processes such as canyon formation and volcanism on their surfaces.

The largest of these five, Titania, is 1,578 km in diameter and the eighth-largest moon in the Solar System, and about 20 times less massive than Earth's Moon. Uranus's irregular moons have elliptical and strongly inclined (mostly retrograde) orbits at great distances from the planet. Ariel is a relatively small satellite and is the brightest moon of Uranus Miranda with a jumbled surface unlike anything in the Solar System, indicates evidence of violent past with possible multiple shattering and reassembly Titania is the largest moon of Uranus and is marked by a few large impact basins Moons of Neptune: Neptune has thirteen known moons, by far the largest of which is Triton, discovered by William Lassell just 17 days after the discovery of Neptune itself. Over a century passed before the discovery of the second natural satellite, called Nereid. Neptune's moons are named for minor water deities in Greek mythology. Unique among all large planetary moons, Triton is an irregular satellite, as its orbit is retrograde to Neptune's rotation and inclined relative to the planet's equator.

The next-largest irregular satellite in the Solar System, Saturn's moon Phoebe, is only 0.03% Triton's mass. Triton is massive enough to have achieved hydrostatic equilibrium and to retain a thin atmosphere capable of forming clouds and hazes. Both its atmosphere and its surface are composed mainly of nitrogen with small amounts of methane and carbon monoxide. Triton's surface appears relatively young, and was probably modified by internally driven processes within the last few million years. The temperature at its surface is about 38K. Inward of Triton are six regular satellites, all of which have prograde orbits in planes that lie close to Neptune's equatorial plane. Some of these orbit among Neptune's rings. The largest of them is Proteus. Neptune also has six outer irregular satellites, including Nereid, whose orbits are much farther from Neptune, have high inclinations, and are mixed between prograde and retrograde. The two outermost ones, Psamathe and Neso, have the largest orbits of any natural satellites discovered in the Solar System to date. Proteus is one of the darkest objects in the Solar System Sinope | astronomy | Britannica.com astronomy THIS IS A DIRECTORY PAGE.

Britannica does not currently have an article on this topic. Learn about this topic in these articles: in Jupiter (planet): Other satellites ...eight outer moons were known, comprising two distinct orbital families. The more distant group—made up of Ananke, Carme, Pasiphae, and Sinope— has retrograde orbits around Jupiter. The closer group—Leda, Himalia, Lysithea, and Elara—has prograde orbits. (In the case of these moons, retrograde motion is in the... JUPITER'S Moons - EnchantedLearning.com Jupiter's Moons Activities, Web Links JUPITER'S MOONS Jupiter has four large moons and dozens of smaller ones (there are about 67 known moons so far). Galileo first discovered the four largest moons of Jupiter, Io, Europa, Ganymede, and Callisto in 1610, using a 20-power telescope; these moons are known as the Galilean moons.

The moons of Jupiter are (in order by their distance from Jupiter): Metis, Adrastea, Amalthea, Thebe, Io, Europa, Ganymede (the biggest), Callisto (the second biggest), Leda (the smallest), Himalia, Lysithea, Elara, Ananke, Carme, Pasiphae, Sinope, and many newly-discovered moons that haven't been named yet. METIS Metis is the closest moon to Jupiter. Metis is 25 miles (40 km) in diameter and orbits 79,500 miles (128,000 km) from Jupiter, within its main ring. Metis and the next moon, Adrastea, are probably the source of the dust in this ring. Metis has a mass of 9 x 1016kg. It orbits Jupiter in 0.294780 (Earth) days; this is faster than Jupiter rotates on its axis. Metis was discovered by Stephen Synnott (Voyager 2) in 1980. ADRASTEA Adrastea is the second-closest moon to Jupiter.

Adrastea is 12 miles (20 km) in diameter and orbits 80,000 miles (129,000 km) from Jupiter, within its main ring. Adrastea and the first moon, Metis, are probably the source of the dust in this ring. Adrastea has a mass of 1.91 x 1016kg. It orbits Jupiter in 0.29826 (Earth) days; this is faster than Jupiter rotates on its axis. Adrastea was discovered by D. Jewitt and E. Danielson (Voyager 2) in 1979. AMALTHEA Amalthea is the third-closest moon to Jupiter and the reddest object in our solar system . Amalthea is 145 x 91 x 83 miles (232 x146 x134 km) in diameter and orbits 112,700 miles (181,300 km) from Jupiter, within the faint Gossamer ring. Amalthea and Thebe likely provide the dust for the Gossamer ring.

Amalthea has a mass of 7.2 x 1021kg. It orbits Jupiter in 0.49817905 (Earth) days and is in synchronous rotation (always keeping the same side facing Jupiter). Amalthea gives off more heat than it receives from the Sun. Amalthea was discovered by Edward Emerson Barnard in 1892. THEBE Thebe is the fourth-closest moon to Jupiter. Thebe is 68 x 56 miles (110 x 90 km) in diameter and orbits 138,000 miles (222,000 km) from Jupiter. Amalthea and Thebe likely provide the dust for the Gossamer ring. Thebe has a mass of 8 x 1017kg. It orbits Jupiter in 0.6745 day (Earth) days and is in synchronous rotation (always keeping the same side facing Jupiter). Thebe was discovered by Stephen Synnott (Voyager 1) in 1980. THE GALILEAN MOONS Two sulfurous eruptions on Io.

Pillan Patera, a volcanic caldera at the left, spews sulfur 86 miles above the surface. IO Io is a large, rocky, volcanically active moon of Jupiter. Its volcanoes spew out molten sulfur, making Io a very colorful moon. It is the innermost of Jupiter's four large moons and the third largest. It has a diameter of 1,942 miles (3,636 km), very close in size to our moon . Io's mean distance from Jupiter is 220,000 miles (422,000 km). It has a mass of 8.93x1022 kg. It takes Io 1.77 days to orbit Jupiter. There is a doughnut-shaped plasma cloud around Jupiter near Io's orbit (known as the "Io plasma torus") This torus is caused by Jupiter's strong magnetic field, which strips ions from Io as it rotates; Io acts like an electrical generator. Io was discovered by Galileo and Marius (independently) in 1610.

Ole Romer (1644-1710) was a Danish astronomer who, in 1675-1676, was the first person to demonstrate that the speed of light is finite. Romer did this by observing eclipses of Jupiter's moon Io as Jupiter's distance from Earth varied through the year. He noticed that the observed period of Io's orbit differed by about 20 minutes; he concluded that this difference was due to the extra distance that the light had to travel to Earth. His calculations put the speed of light at about 225,000 kilometers per second (it is really a bit faster, at 299,792 kilometers per second). EUROPA Europa is a large, dense, icy moon of Jupiter. Europa is the smoothest object in our Solar System . Its surface is covered with long, crisscrossing trackways (but few craters) on water ice. Frozen sulfuric acid has been found on its surface. Europa's diameter is less than 2,000 miles (3,138 km), smaller than the Earth's moon .

It takes Europa 3.55 days to orbit Jupiter (in a synchronous orbit). Its mean distance from Jupiter is about 420,000 miles (670,900 km). Its mass is 4.80x1022 kg. It was discovered by Galileo and S. Marius (independently) in 1610. GANYMEDE Ganymede is the largest moon of Jupiter, a large, icy, outer moon that is scarred with impact craters and many parallel faults. It has a diameter of about 3,400 miles (5,268 km) and orbits Jupiter at a mean distance of 664,000 miles (1,070,000 km). It has a magnetic field and probably has a molten iron core. It takes Ganymede 171.75 hours (7.15 Earth days) to orbit Jupiter. Its mass is 1.48x1023 kg. It was discovered by Galileo and S. Marius (independently) in 1610.

Ganymede is the largest moon in the solar system; it is also larger than the planets Mercury and Pluto. CALLISTO Callisto is a large, icy, dark-colored, low-density outer moon of Jupiter that is scarred with impact craters and ejecta. It has a diameter of about 3,000 miles (4800 km), the second-largest moon of Jupiter; it is roughly the size of Mercury . Callisto has the largest-known impact crater in the Solar System, Valhalla, which has a bright patch 600 km across and rings that go out to almost 3000 km. Callisto orbits Jupiter at a mean distance of 1,170,000 miles (1,883,000 km). Its mass is 1.08x1023 kg. It takes Callisto 400.8 hours = 16.7 days to orbit Jupiter (in a synchronous orbit). Callisto was discovered by Galileo and S. Marius (independently) in 1610. LEDA Leda is Jupiter's ninth and smallest moon.

Leda is 9.9 miles (16 km km) in diameter and orbits at an average of 6,900,000 miles (11,094,000 km) from Jupiter. Leda has a mass of 5.68 x 1015kg. It orbits Jupiter in 238.72 (Earth) days. Very little is known about Leda. Leda was discovered by Charles Kowal in 1974. HIMALIA Himalia is Jupiter's tenth moon. Himalia is 110 miles (170 km) in diameter and orbits 7,000,000 miles (11,480,000 km) from Jupiter. Himalia has a mass of 9.5 x 1018kg. It orbits Jupiter in 250.5662 (Earth) days. Very little is known about Himalia. Himalia was discovered by C. Perrine in 1904. LYSITHEA Lysithea is Jupiter's eleventh moon.

Lysithea is 15 miles (24 km) in diameter and orbits 7,200,000 miles (11,720,000 km) from Jupiter. Lysithea has a mass of 8 x 1016kg. It orbits Jupiter in 259.22 (Earth) days. Very little is known about Lysithea. Lysithea was discovered by S. Nicholson in 1938. ELARA Elara is Jupiter's twelfth moon. Elara is 50 miles (80 km) in diameter and orbits 7,250,000 miles (11,737,000 km) from Jupiter. Elara has a mass of 8 x 1017kg. It orbits Jupiter in 259.6528 (Earth) days. Very little is known about Elara. Elara was discovered by C. Perrine in 1905. ANANKE Ananke is Jupiter's thirteenth moon.

Ananke is 12.5 miles (20 km) in diameter and orbits 13,100,000 miles (21,200,000 km) from Jupiter. Ananke has a mass of 4 x 1016kg. It orbits Jupiter in 631 (Earth) days and is in a retrograde orbit (orbiting opposite to the direction of Jupiter). Very little is known about Ananke. Ananke was discovered by S. Nicholson in 1951. CARME Carme is Jupiter's fourteenth moon. Carme is 18.5 miles (30 km) in diameter and orbits 13,800,000 miles (22,600,000 km) from Jupiter. Carme has a mass of 9 x 1016kg. It orbits Jupiter in 692 (Earth) days and is in a retrograde orbit (orbiting opposite to the direction of Jupiter). Very little is known about Carme. Carme was discovered by S. Nicholson in 1938. PASIPHAE Pasiphae is Jupiter's fifteenth moon.

Pasiphae is 22 miles (36 km) in diameter and orbits 14,600,000 miles (23,500,000 km) from Jupiter. Pasiphae has a mass of 2 x 1023kg. It orbits Jupiter in 735 (Earth) days and is in a retrograde orbit (orbiting opposite to the direction of Jupiter). Very little is known about Pasiphae. Pasiphae was discovered by P. Melotte in 1908. SINOPE Sinope is Jupiter's sixteenth moon. Sinope is 17.5 miles (28 km) in diameter and orbits 14,700,000 miles (23,700,000 km) from Jupiter. Sinope has a mass of 8 x 1016kg. It orbits Jupiter in 758 (Earth) days and is in a retrograde orbit (orbiting opposite to the direction of Jupiter). Very little is known about Sinope. Sinope was discovered by S. Nicholson in 1914.

S/1999 J 1 (a provisional name) The seventeenth and outermost moon; S/1999 J 1 is the smallest-known moon orbiting a major planet. This moon is 3 miles (5 km) in diameter and has an irregular orbit roughly 15 million miles (24 million km) from Jupiter. It orbits Jupiter in 774 (Earth) days and is in a retrograde orbit (orbiting opposite to the direction of Jupiter). It was discovered by Robert S. McMillan et al (at the Spacewatch program at the University of Arizona ) in 2000. Space Today Online - Moons of the Solar System SPACE TODAY ONLINE ~~ COVERING SPACE FROM EARTH TO THE EDGE OF THE UNIVERSE Moons of the Solar System Massive planet Jupiter below the moon Io click NASA image to enlarge A moon is a natural satellite rotating around a planet. While moons vary in size, each moon is much smaller than its planet. Almost 140 moons are known in the Solar System. Several moons are larger than the planet Pluto and two moons are larger than the planet Mercury. There also are many small moons that may be asteroids captured by their planets.

Only Mercury and Venus do not have any moons. By comparison, Earth has one moon and Mars has two. Jupiter has the most of any planet. Saturn is second. Pictures taken by the Hubble Space Telescope suggest there may be even more moons around those outer planets. earth's moon » Largest. The largest moon is Ganymede with a diameter of 3,280 miles, even larger than either of the planets Mercury and Pluto. Saturn's moon Titan is the second largest in the Solar System with a diameter of 3,200 miles, half again as large as Earth's Moon.

The Planets and Their Moons PLANET Jupiter 62 Io, Europa, Ganymede, Callisto, Amalthea, Himalia, Elara, Pasiphae, Sinope, Lysithea, Carme, Ananke, Leda, Metis, Adrastea, Thebe, Callirrhoe, Themisto, Kalyke, Iocaste, Erinome, Harpalyke, Isonoe, Praxidike, Megaclite, Taygete, Chaldene, Autonoe, Thyone, Hermippe, Eurydome, Sponde, Pasithee, Euanthe, Kale, Orthosie, Euporie, Aitne, plus others yet to receive names Saturn 33 Titan, Rhea, Iapetus, Dione, Tethys, Enceladus, Mimas, Hyperion, Prometheus, Pandora, Phoebe, Janus, Epimetheus, Helene, Telesto, Calypso, Atlas, Pan, Ymir, Paaliaq, Siarnaq, Tarvos, Kiviuq, Ijiraq, Thrym, Skadi, Mundilfari,

 Erriapo, Albiorix, Suttung, plus others yet to receive names Uranus 27 Cordelia, Ophelia, Bianca, Cressida, Desdemona, Juliet, Portia, Rosalind, Belinda, Puck, Miranda, Ariel, Umbriel, Titania, Oberon, Caliban, Sycorax, Prospero, Setebos, Stephano, Trinculo, plus others yet to receive names Neptune Triton, Nereid, Naiad, Thalassa, Despina, Galatea, Larissa, Proteus, plus others yet to receive names Pluto 139 Saturn.

When the Cassini spacecraft from Earth arrived at Saturn in 2004, it promptly found two previously unseen moons. They turned out to be the smallest bodies seen until then around the ringed planet. The tiny natural satellites are about 2 miles and 2.5 miles in diameter. That's smaller than the city of Boulder, Colorado. Previously, the smallest moons seen around Saturn were are about 12 miles across. The moons are 120,000 miles and 131,000 miles from the center of planet Saturn between the moons Mimas and Enceladus. The newly discovered bodies were labeled S/2004 S1 and S/2004 S2. Later, they will be given names. The NASA JPL team wondered if S/2004 S1 might not be an object called S/1981 S14 that had turned up in a 1981 Voyager image. Saturn moons » Smallest.

The smallest moon is Deimos, at Mars, only seven miles in diameter, although its size now is rivaled by the small shepherd moons discovered by Cassini at Saturn and by others yet to be counted and named in the rings around Jupiter, Saturn and other giant gas planets in the outer Solar System. There may be tiny moons as small as only around a mile across. Pluto. Charon is the moon closest in size to its planet, Pluto. Earth's Moon is second in that comparison. Neptune. The interplanetary probe Voyager 2 in 1989 found six previously-unknown moons orbiting Neptune. They ranged in diameter from 33 miles to 250 miles. In 1991, they were named Naiad, Thalassa, Despina, Galatea, Larissa, Proteus. The names Galatea and Larissa were controversial since asteroids previously had been given those names. Names are assigned by the nomenclature committee of the International Astronomical Union (IAU). Triton. Before Voyager 2, astronomers knew Neptune had two moons, Triton and Nereid.

With a surface temperature of –391 degrees, Triton was found by Voyager 2 to have a thin veneer of methane and nitrogen on top of water ice on its surface. Triton had been thought to have a diameter of 2,361 miles, close in size to Earth's Moon, but turned out to be smaller, around 1,690 miles. Nereid is 210 miles in diameter. Pan. A new moon only 12 miles in diameter was discovered in 1990 circling the planet Saturn. It was Saturn's 18th and most distant moon. Photos of the planet, moons and rings, left over from the 1981 Saturn flyby by Voyager 2, had been filed away at NASA's Ames Research Center in Mountain View, California, for a decade. A planetary scientist was tipped off to Pan's presence by a disturbance in a 200-mi.-wide gap — Encke's Gap — in Saturn's outermost A ring. Pan's gravity moved particles in the large A ring, creating a gap with waves along the edges like the wake of a motorboat.

Checking the wavy edges, he calculated the probable position and mass of the moon and compared them with Voyager 2 positions and camera angles in 1980-81. When finally uncovered, the moon stood out as a small bright spot in 11 pictures among 30,000 photos scanned by a computer. In 1991, the moon officially was named Pan. It was the second time since Neptune was discovered in 1894 that a gravity disturbance had been used to pinpoint a previously-unknown Solar System body. Inner Solar System. The inner Solar System includes the planets Mercury, Venus, Earth and Mars. Of all the known moons in our Solar System, only three are in the inner region. Mars has two. Earth has one. Mercury and Venus are the only planets without moons. The outer Solar System includes Jupiter, Saturn, Uranus, Neptune and Pluto and the rest of the moons. More moons are discovered each year in the outer Solar System by astronomers using ever more powerful equipment. Atmospheres. Most moons are airless, but Jupiter's Io, Saturn's Titan and Neptune's Triton seem to have atmospheres. Titan may be flooded with an ocean of liquid ethane.

Triton may be covered by an ocean of liquid nitrogen. Io seems to have a thin sulphur dioxide atmosphere from volcanos. Titan. Titan appears to have an organic chemistry in its atmosphere which may resemble the primitive Earth before the dawn of life. It is the only moon known to have a thick, organic-rich nitrogen atmosphere. Surface temperature is around –290 degrees Fahrenheit. Solar System's moons are listed below: Exploring the Moons of the Outer Solar System The moons of the outer planets are popular targets with planners of future spaceflights. Jupiter has more moons than any other planet. Its best known moons are the four large planet-sized bodies Io, Europa, Ganymede and Callisto. jupiter » Callisto is the outermost of the four and the most heavily cratered body in the Solar System. It may have a vast water ocean indside. Io is innermost of the four. This sulfurous moon is the most volcanic world in our Solar System. It is peppered with hundreds of volcanoes, several of which might be active at any given moment. Europa has an icy surface that may hide a layer of warm slush or even liquid water.

That would make it one of the few places in the Solar System with that life-sustaining liquid. Ganymede is the largest moon of Jupiter and the largest moon in the Solar System. In fact, Ganymede is larger in diameter than the planet Mercury and much larger than the planet Pluto. Ganymede has its own magnetic field. Saturn has some unique moons. Here are some examples: Titan is Saturn's largest moon. Mimas has an enormous crater – probably a hole caused by a meteorite. Enceladus has a very bright surface. It may have active water volcanoes. Tethys has a canyon running three-quarters of the way around its surface. That means it may once have been split almost in half. Dione and Rhea have wispy white markings on one side. Hyperion is oddly shaped and the length of its day is constantly changing. Iapetus is half bright and half dark. Pan, by comparison, is a very tiny moon. Its diameter is only 20 km, which on the sale above would be only half the size of a BB. Uranus' moons are eye-openers. They have statuesque mountains towering more than ten miles high. Incredibly deep valleys.

Vast plains, some with a mysterious dark surface. Moon diameters range from a bit fatter than 25 miles up to about 1,100 miles.

Question: Sinope and Carme are two satellites of which planet?
Answer: Jupiter